![]() In this section we learn about magnetism. You may ask why this section isn't its own section, and why it falls under electricity. Well that's for you to find out! So read away! We have a special guest in this section - his name is Mr. Magneto. Once again, our timing is impeccable. There he is right now: "Hello Magneto!" "Do I know you?" "Yes you do, don't you remember we spoke on the phone, the stuff about magnetism???" "Oh yes! What did you want to ask?" "Just about everything. Let us start off with magnetism - what is it?" "Well, that is a tough question but I'll try to answer it. Magnetism is basically the property of an object being able to attract another object. Now this definition is a simple one. A more precise definition would explain that the two substances that attract must be magnetic." "You mentioned a magnetic substance. What is it?" "A magnetic substance is a substance that displays magnetic properties. It attracts other magnetic objects. Before I go on, let me explain some important properties of magnets. Every natural magnet has both a North pole and South pole - a lot like the Earth. A characteristic property of the area around the magnet where it has a magnetic force (magnetic field) is that the magnetic field, or field lines travel from North to South - much like electric current flows from negative to positive. Another characteristic of magnets is that when two magnets attract, the magnets only attract when the North pole of one magnet is beside the South pole of another magnet, or vice-versa. Thinking back to the electric charge section, this is like how a negative charge likes a positive charge, but does not like another negative charge. Then similarly, when two magnets are placed say North to North, or South to South, they repel each other. If you don't believe me then try it yourself It really is quite a neat experiment."
"Well Magneto, you've simplified some of the characteristics of magnets for me, now can you tell me a bit more about magnetic substances, as I initially asked?!" "Oh yes, of course. To be a magnetic substance a substance must have a North pole and a South pole naturally. Thus a magnet can only be a magnet if it is made to be a magnet. Why some substances are magnetic is very complex. It has to do with the electron spin in an atom. In fact, there are only three substances in the world that can become magnetic: Iron, Nickel, and Cobalt. Now these materials can either come out of the Earth magnetic, or they can be induced to be magnetic. If you have an iron magnet and a nickel nail (which is a magnetic substance, but does not experience a magnetic field) that nail will become attracted to the magnet. However, another nail may now be picked up by the attached nail In other words, you do not need to pick up the spare nail from the main magnet, you can pick it up by using the nail that has already been induced. You should try to do this experiment as well, really quite an intriguing experiment." "Thank you." We will speak to Magneto again in the next section, where we will find out if there really is a link between man and monkey. Wait a moment, that is not right! What I meant to say was, we will try to find a link between electricity and magnetism. So to find out if this adventure is true, or just another conspiracy, click below! ![]()
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